The Hawk HB544Z.628 is a rear-axle set of Performance Ceramic street pads for Audi quattro owners who want a cleaner, quieter daily driver without giving up stopping power. The ceramic compound is developed to meet and exceed today's ceramic brake pad users' strict low noise and ultra-low dust performance specifications. For a buyer, the payoff over a stock or basic replacement pad is less wheel dust, less squeal, and reduced pad wear and extended rotor life, which stretches the time between rear brake jobs. Before ordering, check your rear rotor diameter and caliper package against the manufacturer's application guide, since rear fitment varies by model year and brake setup. Long-tail searches this pad fits include "ultra-low dust ceramic rear brake pads Audi A4 quattro," "Hawk PC rear pads B6 A4," and "Audi quattro rear brake pad upgrade."
Installation is a practical weekend job, but the rear caliper is the tricky part. Owners on user forums working on B6-generation A4 rear brakes report that the rear pads are easy to replace, with one exception: an 8mm internal hex bolt on the lower side of the hub spindle becomes very hard to reach if you also replace the rotor. Expect to use a 13mm and 15mm open ended wrench to loosen the slide bolts and slide the caliper off. Retracting the rear piston is where most owners run into trouble. On older mechanical rear calipers, forum members describe needing a dedicated retraction tool, or needle nose pliers, and forcing the piston inward while turning it is the common technique. On electronic parking brake models, owners retract the caliper with software, open the caliper, and then close it again with software, so plan for a scan tool before you start.
It depends on the rear caliper design. Owners on user forums say cars with an electronic parking brake need the caliper motor retracted through software, while older mechanical rear calipers can be wound back with a retraction tool or, in some cases, needle nose pliers.
Owners on user forums report that the rear slide bolts are removed with 13mm and 15mm open-end wrenches, which keeps the job to basic hand tools.
Rear pad swaps are a moderate DIY job, most of the difficulty is in the caliper. Gather 13mm and 15mm open-end wrenches, a rear caliper piston retraction tool or pliers, and a scan tool if your car has an electronic parking brake. Owners on user forums warn that if you are replacing the rotor too, the lower 8mm internal hex bolt holding the caliper carrier can be hard to reach, so plan extra time for it. Clean and lube the slide pins and pad contact points before reassembly, and pump the brake pedal before driving to seat the pads.
